Various systems exist for removing support material from a 3D printed part. These systems often relate to methods for agitating a 3D printed part in a liquid media designed to erode support material surrounding the part. Additional known methods of support removal for three dimensional objects include raising and lowering temperature in a support removal tank to melt the support material, where the support material has a lower melting point than the part. Known systems may utilize a single tank into which the raw part is submerged, or they may include multiple tanks having different properties, including differing temperature or liquids.
U.S. Pat. No. 8,636,850 to Narovlyansky discloses a method for removing the support structures from 3D objects using a liquid jet. The '850 process generally involves inserting two or more objects made by solid freeform fabrication into a cell having an inlet to receive a high-pressure liquid jet located at a top side of the cell and a plurality of draining perforations at the circumferential wall of the cell.
U.S. Pat. No. 8,459,280 to Swanson discloses a support structure removal system comprising a reservoir tank and base unit. The vessel comprises a vessel body, a porous floor configured to retain a 3D part, and an impeller rotatably mounted below the porous floor. The impeller is rotated under magnetic force to agitate the solution around the part. Further, the tank may have a means for adjusting pH and temperature to promote support removal.
U.S. Pat. No. 7,546,841 to Tafoya discloses a device for support removal using liquid agitation and heat in a tank. Communication between a thermocouple in the tank and a microprocessor monitors the temperature in the tank and adjusts conditions accordingly.
The above systems often require manual adjustment throughout the process to adjust for various parts. The above systems may be optimally designed for certain types of parts, and may work well for parts of known and tested sizes, shapes and materials. However, when new types of parts are introduced to the system, much adjustment in setting parameters such as heat, pH, and time is required on the part of the operator to optimize efficient use of energy and time.
Therefore, the drawbacks of the current support removal systems include a lack of efficiency when used for a wide variety of parts. Further, movement of the center of mass of the part throughout the tank increases inefficiency and provides an opportunity for delicate parts to collide with the walls of the tank or components of the machine. Such collisions may cause the part to fracture, and also increase inefficiency through uncontrolled movement within the tank.
Efficient support removal for a wide variety of materials and part shapes and sizes requires a system that is responsive to changes in the part and the working environment surrounding the part. Further, a system is desired that can measure the parameters of the part, either directly or indirectly, and adjust automatically to unique properties of each part. Therefore, a need exists for a support removal machine that can efficiently handle the wide and expanding variety of part types encountered in the fast-growing field of three dimensional printing.